The present invention relates to a method for positioning moving vehicles and for exchanging communications between these vehicles and a central station. It applies to the monitoring of the movement of vehicles carrying dangerous or precious materials over what can be a relatively vast territory.
This method permits a highly reliable, immediate transmission of different alarms occurring on each vehicle, particularly the stoppage, breakdown or exposure to hostile elements. The invention also permits a bilateral sound link between the vehicle and the central station. The latitude and longitude position of the vehicle is accurately known at all times and the distance covered from its starting point is indicated to the central station, which can store this data over a period of time.
At present, no very accurate method for monitoring the movements of vehicles is known. The best known method, which is unfortunately not very efficient, consists of transmitting to a central station the call signal of the vehicle, the distance covered by taking the mileage information from the vehicle gearbox, as well as possible alarms on board the vehicle. This method does not permit an accurate latitude and longitude positioning of the vehicle.